共查询到20条相似文献,搜索用时 15 毫秒
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A Rapidly Self‐Healing Supramolecular Polymer Hydrogel with Photostimulated Room‐Temperature Phosphorescence Responsiveness 下载免费PDF全文
Hui Chen Prof. Xiang Ma Dr. Shuaifan Wu Prof. He Tian 《Angewandte Chemie (International ed. in English)》2014,53(51):14149-14152
Development of self‐healing and photostimulated luminescent supramolecular polymeric materials is important for artificial soft materials. A supramolecular polymeric hydrogel is reported based on the host–guest recognition between a β‐cyclodextrin (β‐CD) host polymer (poly‐β‐CD) and an α‐bromonaphthalene (α‐BrNp) polymer (poly‐BrNp) without any additional gelator, which can self‐heal within only about one minute under ambient atmosphere without any additive. This supramolecular polymer system can be excited to engender room‐temperature phosphorescence (RTP) signals based on the fact that the inclusion of β‐CD macrocycle with α‐BrNp moiety is able to induce RTP emission (CD‐RTP). The RTP signal can be adjusted reversibly by competitive complexation of β‐CD with azobenzene moiety under specific irradiation by introducing another azobenzene guest polymer (poly‐Azo). 相似文献
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Lei Ding Shufang Wang Wenjie Wu Yuehan Hu Cuihong Yang Ming Tan Deling Kong Zhimou Yang 《中国化学》2011,29(10):2182-2186
Self‐assembly prevails in nature and learning from nature will lead to biofunctional materials. Inspired by the protein of elastin, we reported in this study on a supramolecular hydrogel bearing the elastin repeating peptide of VPGAG. The visco‐elasticity property, morphology of the nanostructures, and aromatic stacking in the self‐assembled nanostructure were characterized by a rheometry, transmission electron microscope (TEM), and fluorescence microscope, respectively. The biocompatibility of the gelator was also proved by an MTT assay. Though the supramolecular hydrogel failed to exhibit a high elasticity like elastin, the thixotropic hydrogel might have potentials for the applications in fields of cell culture, controlled‐drug release, etc. 相似文献
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Two‐Photon‐Responsive Supramolecular Hydrogel for Controlling Materials Motion in Micrometer Space 下载免费PDF全文
Tatsuyuki Yoshii Dr. Masato Ikeda Prof. Dr. Itaru Hamachi 《Angewandte Chemie (International ed. in English)》2014,53(28):7264-7267
Spatiotemporal control of fluidity inside a soft matrix by external stimuli allows real‐time manipulation of nano/micromaterials. In this study, we report a two‐photon‐responsive peptide‐based supramolecular hydrogel, the fluidity of which was dramatically controlled with high spatial resolution (10 μm×10 μm×10 μm). The off–on switching of the Brownian motion of nanobeads and chemotaxis of bacteria by two‐photon excitation was successfully demonstrated. 相似文献
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An “Ingredients” Approach to Functional Self‐Synthesizing Materials: A Metal‐Ion‐Selective,Multi‐Responsive,Self‐Assembled Hydrogel 下载免费PDF全文
Dr. Jianwei Li Ivica Cvrtila Mathieu Colomb‐Delsuc Dr. Edwin Otten Prof. Dr. Sijbren Otto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(48):15709-15714
New methodology for making novel materials is highly desirable. Here, an “ingredients” approach to functional self‐assembled hydrogels was developed. By designing a building block to contain the right ingredients, a multi‐responsive, self‐assembled hydrogel was obtained through a process of template‐induced self‐synthesis in a dynamic combinatorial library. The system can be switched between gel and solution by light, redox reactions, pH, temperature, mechanical energy and sequestration or addition of MgII salt. 相似文献
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DNA‐Grafted Supramolecular Polymers: Helical Ribbon Structures Formed by Self‐Assembly of Pyrene–DNA Chimeric Oligomers 下载免费PDF全文
Yuliia Vyborna Mykhailo Vybornyi Dr. Alexander V. Rudnev Prof. Dr. Robert Häner 《Angewandte Chemie (International ed. in English)》2015,54(27):7934-7938
The controlled arraying of DNA strands on adaptive polymeric platforms remains a challenge. Here, the noncovalent synthesis of DNA‐grafted supramolecular polymers from short chimeric oligomers is presented. The oligomers are composed of an oligopyrenotide strand attached to the 5′‐end of an oligodeoxynucleotide. The supramolecular polymerization of these oligomers in an aqueous medium leads to the formation of one‐dimensional (1D) helical ribbon structures. Atomic force and transmission electron microscopy show rod‐like polymers of several hundred nanometers in length. DNA‐grafted polymers of the type described herein will serve as models for the development of structurally and functionally diverse supramolecular platforms with applications in materials science and diagnostics. 相似文献
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Reversible Supramolecular Surface Attachment of Enzyme–Polymer Conjugates for the Design of Biocatalytic Filtration Membranes 下载免费PDF全文
Negar Moridi Prof. Dr. Philippe F.‐X. Corvini Prof. Dr. Patrick Shahgaldian 《Angewandte Chemie (International ed. in English)》2015,54(49):14800-14804
To be used successfully in continuous reactor systems, enzymes must either be retained using filtration membranes or immobilized on a solid component of the reactor. Whereas the first approach requires large amounts of energy, the second approach is limited by the low temporal stability of enzymes under operational conditions. To circumvent these major stumbling blocks, we have developed a strategy that enables the reversible supramolecular immobilization of bioactive enzyme–polymer conjugates at the surface of filtration membranes. The polymer is produced through a reversible addition–fragmentation transfer method; it contains multiple adamantyl moieties that are used to bind the resulting conjugate at the surface of the membrane which has surface‐immobilized cyclodextrin macrocycles. This supramolecular modification is stable under operational conditions and allows for efficient biocatalysis, and can be reversed by competitive host–guest interactions. 相似文献
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Jing Zheng Peng Xiao Wei Liu Jiawei Zhang Youju Huang Tao Chen 《Macromolecular rapid communications》2016,37(3):265-270
Development of self‐healing polymers with spontaneous self‐healing capability and good mechanical performance is highly desired and remains a great challenge. Here, mechanical robust and self‐healable supramolecular hydrogels have been fabricated by using poly(2‐dimethylaminoethyl methacrylate) brushes modified silica nanoparticles (SiO2@PDMAEMA) as multifunctional macrocrosslinkers in a poly(acrylic acid) (PAA) network structure. The SiO2 nanoparticles serve as noncovalent crosslinkers, dissipating energy, whereas the electrostatic interactions between cationic PDMAEMA and anionic PAA render the hydrogel self‐healing property. This process provides a simple and broadly applicable strategy to produce mechanical strong and self‐healable materials.
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Li J Carnall JM Stuart MC Otto S 《Angewandte Chemie (International ed. in English)》2011,50(36):8384-8386
Stacks of macrocycles, assembled using reversible disulfide-bond formation, are covalently captured by photoinitiated exchange of disulfide bonds, inducing the formation of hydrogels. This strategy allows access to structures beyond the thermodynamic minima traditionally targeted by dynamic combinatorial chemistry. 相似文献
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Artur Ciesielski Gaël Schaeffer Anne Petitjean Dr. Jean‐Marie Lehn Prof. Paolo Samorì Prof. 《Angewandte Chemie (International ed. in English)》2009,48(11):2039-2043
Bicomponent supramolecular polymers , consisting of two alternating molecules bridged through six H‐bonds, are observed by STM at the solid–liquid interface. Control of the geometry of the 1D architecture was obtained by using two different connecting molecules with different conformational rigidity, affording either linear (see picture, left) or zigzag (right) motifs.
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Marion K. Müller Luc Brunsveld Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(16):2921-2924
Binding bacteria : Discotic molecules self‐assemble into columnar supramolecular polymers that show strong polyvalent binding to bacteria by virtue of mannose ligands attached at their periphery (orange; see picture). The reversible formation of the supramolecular polymers allows simple mixing of differently substituted monomers and the optimization of bacterial aggregation.
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Carboxylate‐Driven Supramolecular Assemblies of Protonated meso‐Aryl‐Substituted Dipyrrolylpyrazoles 下载免费PDF全文
Prof. Hiromitsu Maeda Kengo Chigusa Dr. Ryohei Yamakado Dr. Tsuneaki Sakurai Prof. Shu Seki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(26):9520-9527
Dipyrrolylpyrazole (dpp) derivatives possessing an aryl ring at the pyrazole 4‐position were synthesized. Upon protonation, modified dpp derivatives formed a variety of assembled structures through complexation with carboxylates, as observed by single‐crystal X‐ray and synchrotron XRD analyses. In particular, the complexation of protonated dpp species possessing long alkyl chains with dicarboxylates resulted in highly ordered assembled structures, the packing modes of which as lamellar structures were controlled by the lengths of the spacer units between two carboxylate moieties. The charge‐carrier transporting properties of the solid materials were also controlled by bound anions, including dicarboxylates. 相似文献
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《Macromolecular rapid communications》2017,38(9)
There is a significant cost to mitigate the infection and inflammation associated with the implantable medical devices. The development of effective antibacterial and anti‐inflammatory biomaterials with novel mechanism of action has become an urgent task. In this study, a supramolecular polymer hydrogel is synthesized by the copolymerization of N‐acryloyl glycinamide and 1‐vinyl‐1,2,4‐triazole in the absence of any chemical crosslinker. The hydrogel network is crosslinked through the hydrogen bond interactions between dual amide motifs in the side chain of N‐acryloyl glycinamide. The prepared hydrogels demonstrate excellent mechanical properties—high tensile strength (≈1.2 MPa), large stretchability (≈1300%), and outstanding compressive strength (≈11 MPa) at swelling equilibrium state. A simulation study elaborates the changes of hydrogen bond interactions when 1‐vinyl‐1,2,4‐triazole is introduced into the gel network. It is demonstrated that the introduction of 1‐vinyl‐1,2,4‐triazole endowes the supramolecular hydrogels with self‐repairability, thermoplasticity, and reprocessability over a lower temperature range for 3D printing of different shapes and patterns under simplified thermomelting extrusion condition. In addition, these hydrogels exhibit antimicrobial and anti‐inflammatory activities, and in vitro cytotoxicity assay and histological staining following in vivo implantation confirm the biocompatibility of the hydrogel. These hydrogels with integrated multifunctions hold promising potential as an injectable biomaterial for treating degenerated soft supporting tissues.
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Spatial Structuring of a Supramolecular Hydrogel by using a Visible‐Light Triggered Catalyst 下载免费PDF全文
Dr. Chandan Maity Wouter E. Hendriksen Prof. Dr. Jan H. van Esch Dr. Rienk Eelkema 《Angewandte Chemie (International ed. in English)》2015,54(3):998-1001
Spatial control over the self‐assembly of synthetic molecular fibers through the use of light‐switchable catalysts can lead to the controlled formation of micropatterns made up of hydrogel structures. A photochromic switch, capable of reversibly releasing a proton upon irradiation, can act as a catalyst for in situ chemical bond formation between otherwise soluble building blocks, thereby leading to fiber formation and gelation in water. The use of a photoswitchable catalyst allows control over the distribution as well as the mechanical properties of the hydrogel material. By using homemade photomasks, spatially structured hydrogels were formed starting from bulk solutions of small molecule gelator precursors through light‐triggered local catalyst activation. 相似文献
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Recognition‐Mediated Hydrogel Swelling Controlled by Interaction with a Negative Thermoresponsive LCST Polymer 下载免费PDF全文
Khaled Belal Dr. François Stoffelbach Joël Lyskawa Matthieu Fumagalli Prof. Dominique Hourdet Alba Marcellan Lieselot De Smet Dr. Victor R. de la Rosa Prof. Graeme Cooke Prof. Richard Hoogenboom Prof. Patrice Woisel 《Angewandte Chemie (International ed. in English)》2016,55(45):13974-13978
Most polymeric thermoresponsive hydrogels contract upon heating beyond the lower critical solution temperature (LCST) of the polymers used. Herein, we report a supramolecular hydrogel system that shows the opposite temperature dependence. When the non‐thermosesponsive hydrogel NaphtGel, containing dialkoxynaphthalene guest molecules, becomes complexed with the tetra cationic macrocyclic host CBPQT4+, swelling occurred as a result of host–guest complex formation leading to charge repulsion between the host units, as well as an osmotic contribution of chloride counter‐ions embedded in the network. The immersion of NaphtGel in a solution of poly(N‐isopropylacrylamide) with tetrathiafulvalene (TTF) end groups complexed with CBPQT4+ induced positive thermoresponsive behaviour. The LCST‐induced dethreading of the polymer‐based pseudorotaxane upon heating led to transfer of the CBPQT4+ host and a concomitant swelling of NaphtGel. Subsequent cooling led to reformation of the TTF‐based host–guest complexes in solution and contraction of the hydrogel. 相似文献